Answer:
Shortest side = 39 cm.
Median side = 65 cm.
Longest side = 91 cm.
Step-by-step explanation:
The perimeter in total is 195 cm. The ratio of the sides are 3 : 5 : 7.
First, find how much parts there are as a whole, by combining the ratios:
3 + 5 + 7 = 15 parts.
Divide the total of parts from the total measurement:
195/15 = 13
Each part has the measurement of 13 cm.
1 part = 13 cm.
Use the following ratio to solve for each of the sides:
Shortest side: 3
3 x 13 = 39
Shortest side = 39 cm.
Median side: 5
5 x 13 = 65
Median side = 65 cm.
Longest side: 7
7 x 13 = 91
Longest side = 91 cm.
Check. Combine all side measurements together. They should equal 195:
39 + 65 + 91 = 195
(39 + 65) + 91 = 195
(104) + 91 = 195
195 = 195 (True).
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Answer: r = C/(2pi)
This is the same as writing 
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Explanation:
pi is some number (approximately 3.14) which means 2pi is also some number (roughly 6.28)
Saying c = 2pi*r means we have 2pi times r, and the result is the circumference c. To isolate r, we'll undo the multiplication. We'll undo it by dividing both sides by 2pi like so
C = 2pi*r
C/(2pi) = r
r = C/(2pi)
in which we can write it like 
So whatever C is, we divide it over 2pi (aka roughly 6.28) to get the radius.
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Extra Info (Optional Section):
As an example, let's say the circumference of the circle is 628 feet. This means the distance around the circle is 628 feet. So C = 628 would lead to...
r = C/(2pi)
r = C/(6.28)
r = 628/(6.28)
r = 100
So the radius would be roughly 100 feet.
Short answer: 98
Remark
when you have an average of 71, it's like saying that you took 4 quizzes and got 71 on all of them.
Step One
Find the total point count for the 4 quizzes.
T_4 = 71 * 4 = 284
Step Two
Create an equation that will give you the necessary point count to average 86.
284 + 5*x = 86 * 9
Why did we do this? It is because you have 9 quizzes altogether. All nine must be something that gives a point count of 86 on each quiz. You have to put together 9 such quizzes with a total count of 774.
Step three
Solve the equation.
284 + 5x = 774 Subtract 284 from both sides.
5x = 774 - 284
5x = 490 Divide by 5
x = 490/5
x = 98
You must get an average of 98 on the next 5 quizzes
Answer: 98 <<<<<
There a app called photo math